One example of such assemblies includes a hydraulic pressure control device for a hydraulically operated brake system for a vehicle. The hydraulic pressure control device generally includes a plurality of solenoid-operated valves. The plurality of solenoid-operated valves are collectively disposed on one base body wherein there are formed fluid passages through which the solenoid-operated valves are connected to each other or the solenoid-operated valves are connected to other components. In this case, as disclosed in JP-A-2000-264192, the plurality of solenoid-operated valves are collectively disposed on one side of the base body, and a cover is fixed to a surface of the base body located on the side of the base body, such that the cover encloses the solenoid-operated valves. Such a hydraulic pressure control device is one example of the assembly according to the present invention.
In the hydraulic pressure control device described above, the base body is generally formed of a metal while the cover is generally formed of a synthetic resin material, from the standpoint of ease of workability, required mechanical strength, etc. The cover is fixed to the base body by a plurality of bolts. In the conventional arrangement, however, it is necessary to form internally threaded holes and through-holes for the bolts in the base body and the cover, respectively, taking a lot of labor in processing. Further, the number of components is undesirably increased, taking a lot of labor in inventory control and fabricating or assembling. Where a seal member is interposed between the cover and the base body for maintaining the fluid-tightness at the fixed portions of the base body and the cover, this results in a lot of labor in the above-described processing, inventory control and fabricating or assembling.
While the above-described explanation is made with respect to the hydraulic pressure control device for the hydraulically operated brake system for the vehicle, problems similar to those indicated above are found in other devices having a structure similar to that of the hydraulic pressure control device, such as a fluid control device of a suspension of the vehicle.
In the above-described hydraulic pressure control device, a housing is provided by a structure in which the base body and the enclosing member are fixed to each other. In this respect, it is considered that the housing is an assembly including a base body and a second member. Further, in the above-described hydraulic pressure control device, the cover is constituted by a hollow member and a closure member which closes one opening of the hollow member. In this respect, it is considered that the housing is an assembly including a base body, a first member, and a second member. These assemblies suffer from problems similar to those described above.